{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T05:06:25Z","timestamp":1787029585885,"version":"build-2736575974"},"reference-count":33,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2021,4,3]],"date-time":"2021-04-03T00:00:00Z","timestamp":1617408000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A new coronavirus (SARS-CoV-2) caused the current coronavirus disease (Covid-19) epidemic. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) is used as the gold standard for clinical detection of SARS-CoV-2. Under ideal conditions, RT-qPCR Covid-19 assays have analytical sensitivity and specificity greater than 95%. However, when the sample panel is enlarged including asymptomatic individuals, the sensitivity decreases and false negatives are reported. Moreover, RT-qPCR requires up to 3\u20136 h with most of the time involved in RNA extraction from swab samples. We introduce CovidArray, a microarray-based assay, to detect SARS-CoV-2 markers N1 and N2 in the nasopharyngeal swabs. The method is based on solid-phase hybridization of fluorescently-labeled amplicons upon RNA extraction and reverse transcription. This approach combines the physical-optical properties of the silicon substrate with the surface chemistry used to coat the substrate to obtain a diagnostic tool of great sensitivity. Furthermore, we used an innovative approach, RNAGEM, to extract and purify viral RNA in less than 15 min. We correctly assigned 12 nasopharyngeal swabs, previously analyzed by RT-qPCR. Thanks to the CovidArray sensitivity we were able to identify a false-negative sample. CovidArray is the first DNA microarray-based assay to detect viral genes in the swabs. Its high sensitivity and the innovative viral RNA extraction by RNAGEM allows the reduction of both the amount of false-negative results and the total analysis time to about 2 h.<\/jats:p>","DOI":"10.3390\/s21072490","type":"journal-article","created":{"date-parts":[[2021,4,3]],"date-time":"2021-04-03T22:03:36Z","timestamp":1617487416000},"page":"2490","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["CovidArray: A Microarray-Based Assay with High Sensitivity for the Detection of Sars-Cov-2 in Nasopharyngeal Swabs"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1780-7823","authenticated-orcid":false,"given":"Francesco","family":"Damin","sequence":"first","affiliation":[{"name":"Istituto di Scienze e Tecnologie Chimiche \u201cGiulio Natta\u201d SCITEC CNR, 20131 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Silvia","family":"Galbiati","sequence":"additional","affiliation":[{"name":"Complications of Diabetes Units, Diabetes Research Institute, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6589-6907","authenticated-orcid":false,"given":"Stella","family":"Gagliardi","sequence":"additional","affiliation":[{"name":"Genomic and Post Genomic Unit, IRCCS Mondino Foundation, 27100 Pavia, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9571-0862","authenticated-orcid":false,"given":"Cristina","family":"Cereda","sequence":"additional","affiliation":[{"name":"Genomic and Post Genomic Unit, IRCCS Mondino Foundation, 27100 Pavia, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7608-3306","authenticated-orcid":false,"given":"Francesca","family":"Dragoni","sequence":"additional","affiliation":[{"name":"Genomic and Post Genomic Unit, IRCCS Mondino Foundation, 27100 Pavia, Italy"},{"name":"Department of Biology and Biotechnology \u201cL. Spallanzani\u201d, University of Pavia, 27100 Pavia, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0735-8331","authenticated-orcid":false,"given":"Claudio","family":"Fenizia","sequence":"additional","affiliation":[{"name":"Department of Pathophysiology and Transplantation, University of Milan, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1476-7689","authenticated-orcid":false,"given":"Valeria","family":"Savasi","sequence":"additional","affiliation":[{"name":"Unit of Obstetrics and Gynecology, L. Sacco Hospital ASST Fatebenefratelli Sacco, 20157 Milan, Italy"},{"name":"Department of Biomedical and Clinical Sciences, University of Milan, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2603-0318","authenticated-orcid":false,"given":"Laura","family":"Sola","sequence":"additional","affiliation":[{"name":"Istituto di Scienze e Tecnologie Chimiche \u201cGiulio Natta\u201d SCITEC CNR, 20131 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marcella","family":"Chiari","sequence":"additional","affiliation":[{"name":"Istituto di Scienze e Tecnologie Chimiche \u201cGiulio Natta\u201d SCITEC CNR, 20131 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,4,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"727","DOI":"10.1056\/NEJMoa2001017","article-title":"A Novel Coronavirus from Patients with Pneumonia in China, 2019","volume":"382","author":"Zhu","year":"2020","journal-title":"N. 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